Micro-Scale Variability Impacts the Outcome of Competition Between Different Modeled Size Classes of Phytoplankton

Frontiers in Marine Science

Anupam Priyadarshi¹  Hidekatsu Yamazaki²  Sandip Mandal³  S. Lan Smith⁴ 

[1] Department of Mathematics, Institute of Science, Banaras Hindu University, Varanasi, India;Department of Ocean Sciences, Tokyo University of Marine Science and Technology, Tokyo, Japan;Public Health Foundation of India, New Delhi, India;Research and Development Centre for Global Change, Japan Agency for Marine-Earth Science and Technology, Yokohama, Japan;

关键词: plankton;    nutrient;    intermittency;    closure model;    eco-physiologyl;   

DOI  :  10.3389/fmars.2019.00259

来源: DOAJ

【 摘 要 】

Previous modeling studies have shown that observed micro-scale (mm) variability of nutrients and phytoplankton biomass can strongly impact the large-scale mean growth response of phytoplankton in ways that cannot be represented by typical models based on the mean field approximation. Also, models accounting for the flexible eco-physiology of phytoplankton predict quite different responses to changing environmental conditions compared to most current (inflexible) models. Combining these two ideas for nutrient-phytoplankton systems we have developed a new “Flexible NP closure model” to represent competition among the three typically observed phytoplankton size classes: pico-, nano-, and micro-phytoplankton. Both micro-scale variability and flexible eco-physiology are expected to impact the competition among these size classes. With this work we begin to address how both these factors determine the size structure and size diversity of phytoplankton in the ocean. Under eutrophic conditions, variability does not impact the modeled growth rate of any size class. On the other hand, under oligotrophic conditions, variability preferentially enhances the biomass of the largest typically observed micro-size class, and reduces the biomass of the smallest nano- and intermediate pico-size classes.

【 授权许可】

Unknown